aFe 3in SS Cat-Back Exhaust | GM Silverado/Sierra 1500 V6/V8 (09-19) (49-44112-P)aFe POWER is proud to introduce the Apollo GT Series dual rear exit cat back exhaust system for the 2014 2019 GM Silverado Sierra 1500 with V6 4. 3L V8 5. 3L engines. This cat back exhaust system is constructed out of 3" 100% MIG welded, mandrel bent, stainless steel tubing for maximum flow. The smooth transition bends allow for low turbulence, increasing horsepower, torque and improving throttle response. In testing, this system resulted in gains up